Contaminant plug for medical instrument sterilization containers

ABSTRACT

A medical instrument sterilization container (10) is provided which includes a port (18). A removable filter (32) is received within port (18) to enable sterilization of instruments placed within container (10). A removable plug (48) replaces filter (32) to enable container (10) to be used to transport instruments without leaking of fluids therefrom.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.08/455,201, filed May 31, 1995, now U.S. Pat. No. 5,954,219 and entitled"Contaminant Plug for Medical Instrument Sterilization Containers" byRobert L. Nichols, William H. Patterson and Keith F. Lindsey, nowpending; which is a divisional of U.S. application Ser. No. 08/140,215,filed Oct. 21, 1993, and entitled "Contaminant Plug for MedicalInstrument Sterilization Containers" by Robert L. Nichols, William H.Patterson and Keith F. Lindsey, now U.S. Pat. No. 5,474,738, issued Dec.12, 1995; which is a continuation of U.S. application Ser. No.07/664,352, filed Mar. 4, 1991, and entitled "Contaminant Plug forMedical Instrument Sterilization Containers" by Robert L. Nichols,William H. Patterson and Keith F. Lindsey, now U.S. Pat. No. 5,324,489,issued Jun. 28, 1994.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the field of medicalinstrument sterilization containers, and more particularly to acontaminant plug for medical instrument sterilization containers.

BACKGROUND OF THE INVENTION

It is common practice in hospitals and other medical environments tosterilize medical instruments with steam or other sterilizing gases suchas ethylene oxide (ETO). Sterilization containers provide a convenientenclosure in which the sterilization can be performed. Additionally,sterilization containers can be used as a storage and containment devicefor moving contaminated instruments from one location to another, whilereducing the probability of cross-contaminating the surroundingenvironment. Finally, during the transfer of contaminated instrumentsafter surgery, sterilization containers can also be used for soakingmedical instruments to prevent blood and other contaminants from dryingon the instruments.

Sterilization containers normally have bottom housings with a bottom andsidewalls, removable lids, ports for the passage of sterilization gasesand filter means for preventing and inhibiting contaminants fromentering the container after sterilization. Containers generally haveone or two ports in the lid and one or two ports in the bottom. Both topand bottom ports are needed if the container is to be used for gravitysteam or ethylene oxide gas sterilization. In gravity steam processes,steam gases enter the top of the sterilizing container and push air downand out. The lower port is therefore required for air and steam to exitthe container. When utilizing ethylene oxide gas sterilization, both topand bottom ports are required during the aeration process in which airis passed through a container to remove residual ethylene oxide gasremaining after sterilization.

The need for both top and bottom ports in the gravity steam and ethyleneoxide processes reduces the utility of the sterilization container forsoaking and transportation applications. If the container is to beutilized as a receptacle for soaking instruments after surgery, or fortransporting contaminated instruments, the bottom or outlet ports willcreate problems. It has been recognized in the medical industry thatfiltered or open ports in the sterilization container bottom may allowsoaking fluids or contaminants to leak or pass through to the outside,thereby contaminating the surroundings. This is even often true withhydrophobic type filters which are generally perceived to pass onlygases and not liquids or solids. Even with such hydrophobic typefilters, there is still the concern that small amounts of contaminantsmay seep through the filter or around the seal.

The need has therefore arisen for a plug which can seal a container portsuch that contaminants, whether liquid or solid, cannot escape. Such aplug would allow the use of a medical instrument sterilization containerwith both top and bottom ports to be used for the transportation ofcontaminated medical instruments without the fear of contamination ofthe surroundings. Further, such a plug would allow a medical instrumentsterilization container having a bottom port to be used for soakingmedical instruments after surgery without leakage.

SUMMARY OF THE INVENTION

According to the invention, a medical instrument sterilization containeris provided which includes a port. A removable filter is provided withinthe port to enable sterilization of instruments placed within thecontainer. A removable plug is provided which replaces or fits above orbelow the filter to enable the container to be used to transportinstruments placed within the container without permitting the passageof contaminants out of the container.

The present invention provides the advantage of sealing a port on amedical instrument sterilization container such that liquid or solidcontaminants cannot escape into the surrounding environment. The medicalinstrument sterilization container can thus be used as a safe means oftransporting contaminated medical instruments without crosscontamination between the exterior and interior of the container.Further, by sealing a medical instrument sterilization containeraccording to the present invention, the medical instrument sterilizationcontainer can be used as a soaking container for soaking instrumentsfollowing their use.

BRIEF DESCRIPTION OF THE DRAWINGS

Other aspects of the invention and their advantages will be discernedwhen one refers to the following detailed description as taken inconjunction with the drawings, in which like numbers identify likeparts, and in which:

FIG. 1 is a perspective view of a medical instrument sterilizationcontainer;

FIG. 2 is a partial section view of the sterilization container of FIG.1;

FIG. 3 is an exploded view of a selected port of the medical instrumentsterilization container of FIG. 1 and the associated filter andretaining cap;

FIGS. 4a and 4b are top and side views of a contaminant plug accordingto a first preferred embodiment;

FIGS. 4c and 4d are respectively exploded and cross-sectional viewsshowing the engagement of the contaminant plug of a first preferredembodiment engaging with a selected port of the medical instrumentsterilization container of FIG. 1;

FIGS. 5a and 5b are respectively top and side views of a contaminantplug according to a second preferred embodiment;

FIGS. 5c and 5d are respectively exploded and cross-sectional viewsdepicting the contaminant plug of a second preferred embodiment engaginga selected port in the medical instrument sterilization container ofFIG. 1;

FIGS. 6a and 6b are respectively top and side views of a contaminantplug according to a third preferred embodiment; and

FIGS. 6c and 6d are respectively exploded perspective andcross-sectional views depicting the contaminant plug of a thirdpreferred embodiment engaging a selected port of the medical instrumentsterilization container of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention are best understood byreferring to FIGS. 1-6 of the drawings, like numerals being used forlike and corresponding parts of the various drawings.

Referring first to FIG. 1, a medical instrument sterilization containeris shown generally at 10, and includes the housing 12 and a removablelid 14. Lid 14 is preferably domed-shaped as shown in FIG. 1; however,lid 14 may also have other configurations as known in the art, such asbeing substantially flat. Removable tray 16 is received within thehousing 12 and is adapted to receive various medical instruments, suchas knives, scissors and the like.

An inlet port 18 is disposed through lid 14 in order to allow thepassage of sterilizing steam and gases therethrough, while inhibiting orpreventing the passage of dirt, dust, bacteria and other contaminantsinto the interior of the container. Two outlet ports, to be discussedbelow, are disposed in the bottom of housing 12. Metal clamps 20 areattached to both sides of the housing 12 and are manually movable toclamp against the side of the lid 14 in order to lock lid 14 to thehousing 12. Suitable sealing surfaces are provided between the housing12 and the lid 14 providing an essentially sealed container when the lid14 is clamped to housing 12.

FIG. 2 is a partially sectioned view of container 10, which depictsoutlet ports 22 and 24 extending from the bottom 25 of housing 12. Ports18, 22 and 24 each include a circular base plate 26 having a pluralityof apertures 28 which communicate with the surrounding atmosphere. Ininlet port 18, base plate 26 is an integral part of domed shaped lid 14.Annular sidewalls 30 form a receptacle which is adapted to receive aremovable filter 32. Removable filter 32 is held tightly within annularsidewalls 30 by a twistable cover 34 which engages a plurality oflocking members 36 disposed around the periphery of the respective port.

Referring next to FIG. 3, an exploded view is shown which demonstratesthe cooperation between a selected port 18, 22 or 24 with an associatedfilter 32 and twistable cover 34. Twistable cover 34 includes fourlocking flanges 37 which extend from a lip member 38. Locking flanges 37are positioned to be rotated into locking members 36 formed around theperiphery of the respective ports 18, 22 or 24. A gripping member orhandle 40 is provided on twistable cap 34 to facilitate its rotationwithin the respective annular sidewalls 30. A typical filter is shownwhich is circular in shape and includes a plastic member having a lip42, plastic cross members 44 and a tab 46 extending from lip 42 to allowmanual insertion or removal from the ports 18, 22 or 24.

Referring next to FIGS. 4a-b, which are top and side views of a firstpreferred embodiment, a contaminant plug 48 is designed to seal aselected port 18, 22 or 24. Plug 48 includes a disk-shape cover plate 50having an upper surface 52, a lower surface 54 and a sidewall 56.Contaminant plug 48 may be made of plastic, metal or any other suitablematerial. An annular flange 58 extends beyond the periphery of sidewall56 and includes four locking flanges 60 which are positioned to engagelocking members 36 disposed around a selected port 18, 22 or 24. A slot62 is formed in sidewall 56 around the periphery of cover plate 50. AnO-ring seal 64, formed of silicone or another suitable compressiblematerial which is contaminant impermeable, is disposed in slot 62. Agripping member 66 is fastened to cover plate 50 by a screw 68.

FIGS. 4c and 4d illustrate in detail the engagement of contaminant plug48 with a selected one of ports 18, 22 or 24. While in the preferredembodiment contaminant plug 48 is shown to be removable, it should beunderstood by persons skilled in the art that removability is not anessential requirement. FIG. 4c is an exploded perspective view of plug48 and the selected port prior to engagement. FIG. 4d is across-sectional view showing contaminant plug 48 inserted into theselected port 18, 22 or 24 and engaged. Contaminant plug 48 is insertedinto the selected port such that O-ring seal 64 is pressed firmlyagainst annular sidewalls of ports 18, 22 and 24. Using gripping member66, contaminant plug 48 can be twisted within sidewalls 30 such thatlocking flanges 60 engage locking members 36. Locking flanges 60 aretightly held by locking members 36 such that O-ring seal 64 prevents thepassage of contaminants from the interior of housing 12 throughapertures 28 of the selected ports 18, 22, or 24.

Contaminant plug 48 may be used by medical personnel in place of filter32 and twistable cover 34, thus allowing medical instrumentsterilization container 10 to be used as a receptacle for soakinginstruments following surgery or for transporting medical instrumentswithout cross contamination with the outside environment. When desired,plugs 48 may be removed or opened, thus allowing the container 10 againto be used in connection with the sterilization of medical instruments.

FIGS. 5a and 5b illustrate top and side views of a second embodiment ofthe present invention. A contaminant plug is shown generally at 70, andincludes a twistable cover 34 and a disk-shaped compression seal 72comprised of silicone or another suitable compressible material.Compression seal 72 is shown as a discrete member inserted directly intoa selected port 18, 22 or 24; however, compression seal 72 may bedirectly fastened to twistable cover 34 to provide a single unit. Ineither case, compression seal 72 is pressed tightly against the base 26of the selected port 18, 22 or 24, thereby sealing off perforations 28.The engagement of compression seal 72 and twistable cover 34 is depictedin FIG. 5c which is an exploded perspective view of contaminant plug 70and a selected port 18, 22 or 24, and FIG. 5d which is a cross-sectionalview showing compression seal 72 and cover 34 engaged in the selectedport. Contaminant plug 70 has the significant advantage of utilizing thetwistable cover 34 already available for retaining filters 32. Further,compression seal 72 may be disposable for convenience.

Turn next to FIGS. 6a and 6b, wherein respective side and top views of asealing disk 74 are shown for use in a third embodiment contaminantplug. Sealing disk 74 includes a circular base plate 76, an annularsidewall 78 formed at an angle to base plate 76, and a lip member 80disposed around the edge of annular sidewall 78. Preferably, a tab 82 isfastened to annular sidewall 78 to aid in the insertion and removal ofsealing disk 74 from a selected port 18, 22 or 24. Sealing disk 74 maybe formed of a plastic or other suitable material that prevents passageof contaminants whether solid, liquid or gaseous.

FIGS. 6c and 6d are respective exploded perspective and cross-sectionalviews showing the engagement of disk 74 and twistable cover 34 in aselected port 18, 22, or 24. Sealing disk 74 is adapted to be insertedwithin sidewalls 30 of the selected port. Lip member 80 can seat on thebottom of housing 12 around the immediate periphery of the selected port18, 22 or 24. A twistable cover 34 then seats within the annularsidewall 78 of sealing disk 74. When twistable cover 34 is twisted suchthat its locking flanges 37 engage with locking members 36 of theselected port 18, 22 or 24, sealing disk 74 is firmly retained providingthe requisite seal. This can be most easily seen by referring to FIG.6c, which is a perspective view showing a sealing disk 74 and anassociated twistable cap 34 inserted and engaged in a selected port 18,22 or 24. Sealing disk 74, when properly engaged with the selected port18, 22 or 24, thereby prevents the communication of contaminants betweenthe interior and exterior of medical instrument sterilization container10.

Thus, the present invention enables a medical instrument sterilizationcontainer having inlet and outlet ports to be sealed to prevent theundesired escape of contaminants into the surrounding area. The presentinvention allows such a medical instrument sterilization container to beused for the safe transport of contaminated medical instruments withoutthe risk of exposing the outside environment. Further, the presentinvention allows a medical instrument sterilization container to be usedas a convenient receptacle for soaking medical instruments followingsuch medical procedures as surgery.

While preferred embodiments of the invention and their advantages havebeen set forth in the above-detailed description, the invention is notlimited thereto, but only by the scope and spirit of the appendedclaims.

What is claimed is:
 1. A method of using a medical instrument andcontaining associated contaminants, comprising:inserting the medicalinstrument into a medical instrument sterilization container, thecontainer comprising a housing, a port defined through the housing andincluding a perforated base, a locking mechanism disposed about aperiphery of the port, a removable filter disposed within the portadjacent the perforated base, and a removable cover disposed adjacentthe port and cooperating with the locking mechanism to lock the filterinto engagement with the perforated base, removing the medicalinstrument from the container, unlocking the removable cover, removingthe filter from the port, inserting a removable sealing member in theport, replacing the removable cover to lock the sealing member intoengagement with the port, and reinserting the medical instrument intothe container.
 2. The method of claim 1, wherein the step of inserting aremovable sealing member comprises attaching the removable sealingmember to the cover.
 3. The method of claim 2, wherein the step ofreplacing the removable cover comprises locking the sealing member intoengagement with an annular sidewall of the port.
 4. The method of claim3, wherein when the sealing member is locked into engagement, thesealing member is disposed between the annular sidewall of the port anda peripheral sidewall of the cover.
 5. The method of claim 1, whereinthe step of inverting a removable sealing member comprises inserting adisk of compressible material adapted to insertably engage the port. 6.The method of claim 1, wherein the step of replacing the removable covercomprises locking the sealing member into engagement with the port. 7.The method of claim 1, wherein the step of replacing the removable covercomprises locking the sealing member into engagement with the perforatedbase.
 8. The method of claim 1, wherein when the sealing member islocked into engagement, the sealing member is disposed between the coverand the perforated base.
 9. The method of claim 1, wherein when thesealing member is locked into engagement, the sealing member ispartially disposed between the cover and the perforated base andpartially disposed between an annular sidewall of the port and aperipheral sidewall of the cover.
 10. The method of claim 1, wherein thestep of inserting a removable sealing member comprises inserting asealing disk comprising a base and an annular sidewall extending fromthe base, the base being adjacent a lower surface of the cover and theannular sidewall being adjacent a peripheral sidewall of the cover. 11.The method of claim 10, wherein the sealing disk further comprises agripping member extending from the annular sidewall of the sealing disk.